Self-locking burglar alarm system



Sept. 17, 1968 M. CONTRERAS 3,402,405

SELF-LOCKING BURGLAR ALARM SYSTEM Filed Jan. 5, 1966 T H- J 5 .1 .l. 2 1 J 26 D49 a4. 9 /2 V /f E A? E D /Z/ I fla I /5 /2 i 6 A26 I /7 F l 24 A? v I /7 5,4 /5 5 /Z INVENTOR dame sens ATTORNEYS,

MA/l/EZ United States Patent 3,402,405 SELF-LOCKING BURGLAR ALARM SYSTEM Manuel Contreras, 2360 Lafayette St., North Bellrnore, N.Y. 11710 Filed Jan. 3, 1966, Ser. No. 518,354 3 Claims. (Cl. 340-274) The present invention generally relates to a burglar alarm system, and more specifically to a burglar alarm and locking device, which is automatically operated when a door, window or the like is opened, to operate an alarm signal.

It is well known that burglars enter homes and stores through doors and windows, and, as such, pose a potential threat to life and property within.

It is therefore an object of the present invention, to provide a novel, strong, durable and compact burglar alarm and lock which will be relatively inexpensive to manufacture, simple and positive in action and yet highly efficient in use.

It is another object of the present invention to provide a burglar alarm and lock wherein the same means for activating an alarm signal also activates a locking device.

It is yet another object of the invention to provide an alarm system that will not operate until tripped by the surreptitious movement of a door, window or the like, and which can be made totally inoperative when so desired.

It is a still further object of the invention to provide an alarm system which is easy to install, without the requirement of special installation equipment.

It is a further object of the present invention to provide a self-contained alarm system, which does not require an external power supply, and which is capable of being placed in locations so as to be relatively tamper-proof.

In accordance with these objects, the present invention provides a means whereby, upon an attempt by a burglar to make an illegal entry, an alarm is activated while simultaneously providing a secondary lock preventing entry of the burglar. The present invention also provides means for making the present invention inoperative during periods of normal door usage. The operation of the novel alarm and locking device is achieved by a spring biasing an arm in position, so that when the door or window is illegally moved, the arm is caused to move through an aperture in a plate fixed to the door jamb, to simultaneously close an electric circuit and activate an alarm.

The above objects as well as other and further objects, features and advantages of the present invention will be manifest in the following detailed description of a preferred embodiment thereof when read in connection with the accompanying drawings which form a part hereof.

In the drawings:

FIG. 1 is a longitudinal section, taken along line 3-3 of FIG. 3, showing the burglar alarm and locking device in the inactivated position;

FIG. 2 is a vertical transverse section, taken along line 2-2 of FIG. 1 of the device shown in FIG. 1; and

FIG. 3 is a fragmentary perspective view, in a reduced scale, showing the present invention installed relative to a door and an adjacent wall.

Referring in detail to the drawings, wherein like and related numerals designate like and related parts throughout the several views, an elongated casing 1, preferably of a dielectric material, is employed, having suitable screw openings through which screws 12 secure casing 1 to a door D. Casing 1 has an open front which is closed by a removable cover 2, adapted to snap securely over casing 1. Cover 2 is provided, at the upper part thereof, with a plurality of concentric holes 20 which permit the transmission of sound or light to the exterior of the casing 1. A horn H is secured to casing 1 by means of a screw 21,

through suitable screw openings in a terminal 14, which is secured to the rear of horn H. Terminal 14 thus forms a conduction path between horn H and easing 1.

A wire 7 leads from horn H to one side of spring terminal 5, which is disposed adjacent and parallel to a spring terminal 5A. Both spring terminals 5 and 5A are secured to the bottom of casing 1. A wire 6 leads from other side of spring terminal 5 to the same side of spring terminal 5A, thus forming a conduction path therebetween. A contact 16 is mounted on the opposite side of spring terminal 5A, and is positioned to engage contact spring 17 when contact spring 17 is activated by movement of an arm 10 described below. Contact spring 17 is secured to casing 1 by a screw 18, which passes through a screw opening in casing 1, thus forming a conduction path between contact spring 17 and easing 1. When the device is in a first position, as shown in FIG. 1, contact spring 17 engages a flanged plate 15, which is mounted to an arm 10 by a screw 13 through a screw opening in flanged plate 15.

Afiixed through hole 22, in flanged plate 15, is one side of coil spring 8, the other side of said coil spring 8 being affixed through hole 23 in casing 1. Coil spring 8 is in tension when the present device is in the first position.

Arm 10 extends through slots 24 and 25 in casing 1 and engages plate 9, which is secured to a door jamb J by a screw 19. When the device is in the first position, the force exerted by coil spring 8 results in arm 10 being biased against plate 9, and plate 9 restrains arm 10 from vertical movement Batteries 3 are inserted within C-shaped spring battery clips 4 so as to be supported thereby. The poles of said batteries 3 are electrically engaged to spring terminals 5 and 5A, Batteries 3 are similar in structure, but are disposed in reversed polarity and are thus electrically connected to horn H. Upon the engagement of contact spring 17 with Contact 16, when the present device is in a second position shown in FIG. 2 by a dotted fragmentary portion of arm 10, horn H is activated, while simultaneously locking arm 10 in plate 9, as shown in the dotted view.

When door D is thus opened, arm 10 will engage an aperture 26 in plate 9, and said arm 10 will slide through slots 24 and 25 and aperture 26 in plate 9, into the second position shown in FIG. 2, thereby causing contact spring 17 to engage contact 16, resulting in the activation of horn H. An angle plate 11, mounted on the underside of arm 10, is suitably disposed to serve as a stop against the overhanging portion of easing 1 when the inventive device is in the aforesaid second position.

The device is readily returned to the closed position by pulling down on a flange 27 of arm 10, thus deactivating horn H, and unlocking the device. Upon a further downward pulling of flange 27 a stop 28, which is mounted on the underside of arm 10, will engage the corner of slot 24, and will thus render the present invention inoperative. In this manner, the alarm system can be made operative only during those periods when usage of the door is not to be expected.

What I claim is:

1. In combination with a door, window, or the like, an alarm and locking device comprising, a housing mounted to said door having openings at the upper and lower surfaces thereof, an arm member extending through both of said openings, a mounting plate secured to said arm member, resilient means secured at one end thereof to the upper surface of said housing and at the other end thereof to said mounting plate for biasing said arm in a first position, a locking plate having an aperture therethrough mounted to the jamb of said door disposed above said housing, signal means mounted to said housing, electrical supply means, a first contact connected to said supply means and said signal means, and a second conmoved;- said arm member comes into registry with said aperture and is urged therethrough into a second. position by said resilient. means, thereby'locking said door and bringing said first and second contacts into electrical con- ,wncctifln'fo'energize said signal means.

' 2. The alarm and signal device as recited in claim 1, wherein said signal means comprise a horn, and said electrical supply means comprise a battery.

3. The alarm and signal device as recited in claim 1, further comprising stop means mountedto said arm memher and adapted to engage with the hole at the lower surface of said housing to place said device in an inoperative position by pulling said arm through said lower hole/ References'lcit'edf f .1 UNITED STATES: PATENTS 410,683 2,521,005 9/1950 Gundlach, 340 274 X 2,675,439 4/1954. -Merchant 340 274X' FOREIGN? PATENTS 372,061 3/1923 Germany 458,687 3/1928 Germany.

JOHN CALDWELL, Primary Examiner. D. L. TRAFTON, Assistant Examiner.

911889 Carhart 340-274 X" 

1. IN COMBINATION WITH A DOOR, WINDOW, OR THE LIKE, AN ALARM AND LOCKING DEVICE COMPRISING, A HOUSING MOUNTED TO SAID DOOR HAVING OPENINGS AT THE UPPER AND LOWER SURFACES THEREOF, AN ARM MEMBER EXTENDING THROUGH BOTH OF SAID OPENINGS, A MOUNTING PLATE SECURED TO SAID ARM MEMBER, RESILIENT MEANS SECURED AT ONE END THEREOF TO THE UPPER SURFACE OF SAID HOUSING AND AT THE OTHER END THEREOF TO SAID MOUNTING PLATE FOR BIASING SAID ARM IN A FIRST POSITION, A LOCKING PLATE HAVING AN APERTURE THERETHROUGH MOUNTED TO THE JAMB OF SAID DOOR DISPOSED ABOVE SAID HOUSING, SIGNAL MEANS MOUNTED TO SAID HOUSING, ELECTRICAL SUPPLY MEANS, A FIRST CONTACT CONNECTED TO SAID SUPPLY MEANS AND SAID SIGNAL MEANS, AND A SECOND CONTACT BIASED BY SAID MOUNTING PLATE OUT OF CONNECTION WITH SAID FIRST CONTACT, WHEREBY WHEN SAID DOOR IS LATERALLY MOVED, SAID ARM MEMBER COMES INTO REGISTRY WITH SAID APERTURE AND IS URGED THERETHROUGH INTO A SECOND POSITION BY SAID RESILIENT MEANS, THEREBY LOCKING SAID DOOR AND BRINGING SAID FIRST AND SECOND CONTACTS INTO ELECTRICAL CONNECTION TO ENERGIZE SAID SIGNAL MEANS. 